// support.js
class Container {
  static of(value){
      return new Container(value)
  }
  constructor(value){
      this._value = value
  }
  map(fn){
      return Container.of(fn(this._value))
  }
}

class Maybe {
  static of(x){
      return new Maybe(x)
  }
  isNothing(){
      return this._value === null || this._value === undefined
  }
  constructor(x){
      this._value = x
  }
  map(fn){
      return this.isNothing() ? this : Maybe.of(fn(this._value))
  }
}
module.exports = { Maybe, Container }